1. Lesson Objective: You will be able to know and identify that an element is a pure substance represented by chemical symbols.

2. Elements & Atoms Elements are pure substances because they are made up of just one type of atom.

3. Periodic Table of Elements The periodic table of elements is the way we organize all the known elements in the universe. They are organized by their physical and chemical properties.

4. Think-Pair-Share

5. What are some patterns that you noticed?

6. Each element has a chemical symbol, which is usually one or two letters representing the element. Chemical Symbols O Oxygen 168 Si Silicon 1428 H Hydrogen 1 1 Hg Mercury 80 201

7. Chemical Symbols If the symbol is one letter, then the letter is always capitalized. O Oxygen 168 H Hydrogen 11 1 letter chemical symbol, always capitalized

8. Chemical Symbols If the symbol is two letters, then the first letter is always capitalized and the second letter is always lowercase. Hg Mercury 80 201 Si Silicon 1428 2 lettered chemical symbol, 1 st is capital, 2 nd is lowercase

9. 1-Letter Chemical Symbols N Nitrogen 7 14 C Carbon 6 12 P Phosphorous 15 31 F Fluorine 9 19 K Potassium 19 39

10. Sc Scandium 21 45 Ag Silver 47 108 He Helium 2 4 Fe Iron 2656 Au Gold 79 197 Ne Neon 1020 2-Letter Chemical Symbols:

11. The chemical symbol represents each element on the periodic table. The symbols are also used to represent elements in chemical formulas and equations. Chemical Symbols + = Na (Sodium) Cl (Chlorine) NaCl (Sodium Chloride)

12. Take another look at your periodic table. Write down 5 elements whose chemical symbol is only one capital letter, and 5 elements whose chemical symbol is one capital letter and one lower case letter.

13. How many elements are in the following substances? H 2 O CON 3 CaO NeCa

14. How many elements are in the following chemical formula? NH 3

15. Which of the following examples is an element? NH 4 or Ne?

16. Partner- Work